This invention relates broadly to wind operated musical instruments and particularly to those musical instruments which are resonant in response to vibrating air columns induced therein to produce tones of various different pitches.
In accordance with the invention disclosed in the '238 patent, a musical instrument is provided that comprises a single mouthpiece, a hollow, outer tubing assembly or horn connected to the mouthpiece and terminating in a bell, and an inner horn assembly comprising an inner horn mounted within the outer tubing assembly at its belled end. The inner horn has an open, upstream end located inside the outer horn and either an open or a closed downstream end projecting outwardly from the belled end of the outer horn. If open, the downstream end of the inner horn could be belled or tubular. In the preferred embodiment disclosed in the '238 patent, the inner horn is in the form of a straight tube which is closed at its outer end by a cap.
It is known that sound vibrations are created at an inlet or mouthpiece of a wind instrument are channeled through an elongated tube whose effective length is configured, that is, lengthened or shortened, to create resonance therein so as to amplify the sound vibrations. The frequencies of the vibrations at which a wind instrument is resonant depend upon the length of the instrument, that is, the length of the tube between its air inlet and its air outlet. This length determines, but is not quite equal to, the effective length of the air column in which the sound waves are formed that, at certain frequencies, cause the instrument to resonate and thereby amplify the sound output of the instrument. To resonate at any given frequency, a conventional instrument must have an effective air column equal in length to an integral multiple of one-half of the wave length of that frequency. This forms the basis for the so-called "harmonic series" of notes that can be resonant and amplified by an instrument having an air column of a given effective length, which series may be expressed by the series of fractions 1/2, 2/2, 3/2, 4/2 . . . n/2, wherein the numerator represents the number of one-half waves formed in the air column.
The common bugle has a single fixed length and is, therefore, capable of resonating only at frequencies within a single harmonic series. It cannot be used to produce a complete major or minor scale. In order to produce major and minor scales and also complete chromatic scales, most wind instruments are provided with mechanisms to change the tube and effective air column Lengths. Such mechanisms usually comprise telescoping slides, openable ports, or depressible or rotatable valve keys to provide openings to differing combinations of tubing sections. Because of the ability to change the effective air column lengths, the instruments can be used to produce multiple sets of harmonic series and thereby to produce complete chromatic scales.
The frequency, and therefore the pitch, of vibration of a wind instrument depends upon the frequency of the input to the instrument. Typically, a wind instrument, including its mouthpiece, is so constructed that one may produce frequencies beginning with the first or second harmonic number and, depending upon the skill of the musician, extending upwardly through several harmonic numbers. One may change the inlet openings so that the frequencies produced tend to be in the higher harmonic ranges. For example, an instrument made by equipping a bass horn with a conventional trumpet mouthpiece may not be usable to play the lower harmonics but could be used for playing higher harmonics than can be obtained using a conventional bass horn mouthpiece. This is because the bass horn mouthpiece is designed to enable one to vibrate the lips at lower frequencies than possible with a trumpet mouthpiece, at the expense of higher frequencies available using a trumpet mouthpiece.
As those skilled in the art are aware, the number of scale notes between the members of a harmonic series decreases as the harmonic number increases. If the harmonic number is raised high enough, an instrument will play adjacent half tone notes. (At even higher harmonics, an instrument would play quarter tones.) This phenomena has been applied since the days of Bach to the manufacture of "natural horns" which, as with bugles, may not have mechanisms to change the length of the instrument tubes but, because they have relatively small mouthpieces in relation to the lengths of their tubes, are readily played in the higher harmonic ranges, from about 5/2 or 6/2 to about 20/2, and can be used to play imperfect scales. (Some of the natural horns may have had one or two small ports used to adjust off-pitch tones.)
Natural horns have the advantage of being playable without manipulation of tube length-changing mechanisms but they are not in general use. This is probably due, at least in part, to their inability to satisfactorily produce a complete scale. A problem with musical wind instruments capable of playing complete scales is that they require considerable skill, patience, and practice to play. Not only must musicians be dexterous with their fingers to reconfigure the instrument tubes, they must also memorize all of the proper positions and coordinate them with their lip movements.
An object of this invention is to provide a musical wind instrument which may be used to play more notes than possible with a conventional instrument having a fixed tube length but which is simpler to play than conventional wind instruments having mechanisms for changing their tube lengths. In a particular aspect of this invention, an object is to provide a musical wind instrument which may be used to play a complete major scale without coordinated mouth and finger operations.
In another aspect of this invention, an object is to provide a musical wind instrument which may be used to produce a complete chromatic scale with a minimum of coordinated mouth and finger operations.
The foregoing objects of this invention are generally the same as the objects of the '238 patent. In accordance with the invention disclosed therein, a musical instrument is provided which comprises a single mouthpiece, a hollow, outer tubing assembly or horn connected to the mouthpiece and terminating in a bell, and an inner horn assembly mounted within the outer tubing assembly at its belled end. In the preferred embodiment disclosed therein, the inner horn assembly comprises a single, tubular inner horn having an open, upstream or proximal end concentrically located inside the outer horn and a closed downstream or distal end located ,adjacent the belled end of the outer horn. In related embodiments, the inner horn can have an open downstream or distal end which can be either belled or tubular. Furthermore, the use of two concentric inner horns for producing additional scale notes was contemplated although I believed at the time the application for the '238 patent was filed that the use of two or more inner horns would be impractical and unnecessary.
Although a musical instrument constructed in accordance with the invention as described in the '238 patent can be somewhat successful in meeting the objects of the invention, such an instrument produced still-retained unpleasant off key notes (e.g. 11/2, 13/2 and 14/2), and would probably be of doubtful commercial utility. Accordingly, a further object of this invention is to improve upon the invention described in the '238 patent.
Another object of this invention is to provide a method for producing an inner horn assembly including a method for determining the length of inner horns thereof.
Other objects of this invention are to provide a wind instrument having a reasonably consistent timbre, playable over a two octave range, having a reasonably true pitch, and playable loud enough to be useful without unduly straining the musician playing it--that is, a wind instrument that is pleasant to listen to and easy to play.